1. Field of the Invention
The present invention relates to an inkjet recording method and an inkjet recording device.
2. Description of the Related Art
Heretofore, in a case of printing onto a nonwoven fabric used in a diaper (also including disposable pants), training pants, an incontinence underwear for adult, or the like, a conventional printing method such as flexography has been applied. In such a conventional printing method, it is difficult to form an image well on the nonwoven fabric since a plate directly comes into contact with the nonwoven fabric. Therefore, after printing on a polypropylene sheet in advance, placing a polypropylene sheet on the nonwoven fabric was a general method.
However, in a case of producing a product by placing the polypropylene sheet on the nonwoven fabric, this leads to a result in which the breathability possessed by the nonwoven fabric becomes impaired. Therefore, in a case where printing of an image having a large area is performed, it was extremely difficult to ensure the breathability.
As one of the methods to solve such a problem, it is conceivable that an image is directly formed on the nonwoven fabric by an inkjet method (for example, refer to JP4425914B and JP2008-516807A). In the inkjet method, since an image is formed by ink droplets (dot) which has been landed by spraying an ink, it is possible to perform drawing without an inkjet head coming into contact with the nonwoven fabric.
As an example of the ink which is used for the nonwoven fabric, or the like, an aqueous ink has been proposed from the past (for example, refer to JP2006-249203A and JP2011-513049A). The aqueous ink has excellent safety for human bodies, compared with a solvent based ink. Therefore, in respect of the safety, the aqueous ink is suitable for an application of a diaper that may come into contact with the skin, and the like.
On the other hand, a method of adding latex in ink is considered as described in JP2011-513049A, from the viewpoint of improvement of the adhesion of an image to the nonwoven fabric. However, in a case where a step of printing onto the nonwoven fabric is established to a manufacturing line, since an image formation is required generally under 200 m/min to 500 m/min of high-speed transport, from the viewpoint of achieving the high productivity, it is difficult to maintain the high productivity by using the aqueous ink. That is, in a case where the aqueous ink is used, in order to fix an image on the nonwoven fabric, water has to be dried, and thus a large-scale drying device is essential for retaining the high productivity.
In addition, a technology in which an ultraviolet curable ink is used for printing onto a cloth is disclosed (refer to JP2012-158683A, JP2008-533217A and JP2003-508277A). The ultraviolet curable ink can solve the problem of drying in the aqueous ink as described above, that is, requiring a large drying device for drying. In other words, since the ultraviolet curable ink is cured at high-speed by an ultraviolet ray, it is possible to considerably simplify a drying (curing) system.